INTRODUCTION: The continuing overall objective of the proposed research is to determine the various molecular mechanisms by which the amount and activity of a specific nonsecreted protein with a known function is regulated in uterine tissue by ovarian hormones. The specific protein to be studied is the enzyme glucose-6-phosphate dehydrogenase (G6PD). SPECIFIC AIMS: 1) To determine the effects of estradiol on the uterine mRNA pools for the enzyme G6PD and to evaluate the possible existence of precursor forms of the G6PD mRNA, 2) To quantify the effects of extradiol and NADP ion on the time required for uterine ribosomes to transit the G6PD and mRNA and to determine the mechanisms by which these effects occur, 3) To isolate and characterize pre-G6PD and then to determine the biological importance of the pre-G6PD and the mechanism by which pre-G6PD is converted to G6PD, and 4) To determine the subcellular site of degradation of uterine G6PD and the mechanism by which estradiol controls this process. METHODS: Uterine mRNA will be isolated and then quantified by immunoprecipitation of G6PD which is produced in a wheat-germ cell-free protein synthesis system using the uterine mRNA. Total translation time of uterine G6PD will be determined by quantification of the time between the initial incorporation of labeled amino acids into nascent proteins and the initial labeling of G6PD in the released protein fraction. The pre-G6PD will be obtained from a "microsomal" pool of G6PD with pre-G6PD properties or from the translation products of the wheat germ system. Inactive intermediates of G6PD synthesis and degradation will be determined using an RIA procedure. SIGNIGICANCE: These studies will permit a better understanding of the overall series of mechanisms by which estradiol can regulate the synthesis of specific proteins in the uterus.